The Sound of Waves (1964)

On a small island, inhabited by only fourteen hundred people, a young fisherman's son, Shinji falls in love with Hatsue, the daughter of the richest and most difficult man on the island. Despite their differences in class, they begin to meet and rumors spread of them having an illicit affair. Soon after, Shinji jumps into a stormy sea to help a ship in distress. The vessel turns out to be owned by Hatsue's arrogant father, who now becomes an understanding and sympathetic parent and allows the two lovers to marry.